Lateral femoral cutaneous nerve syndrome is a nerve condition that causes an altered sensation in the front/side of the thigh.
These symptoms can range from slight to disabling in intensity. Of the nerve disorders affecting the leg, only sciatica occurs more frequently than lateral femoral cutaneous nerve syndrome.
The syndrome is probably not diagnosed as much as it should be because of the difficulty many patients have in describing the symptoms to their doctors.
The lateral femoral cutaneous nerve syndrome has also been called meralgia paresthetica; from the Greek ‘meros’ for thigh, ‘algos’ for pain, and ‘paresthetica’ which means unprovoked sensations. This term, which is still used by many professionals, was first coined in 1895. That means this condition was one of the first nerve entrapment conditions to be named by medical science.
Sigmund Freud is thought to have been a sufferer of this condition. Unfortunately, understanding of this disorder has changed little in the 110 years since Freud complained of his thigh feeling numb.
The lateral femoral cutaneous nerve arises in the upper lumbar spine. It passes the muscles that flex the hip and crosses out of the side of the abdomen by the side of the waist (pelvis). Compression of the nerve can develop at this point vulnerable point, where it crosses from the abdomen to the leg. From there, the nerve supplies sensation to the front and side of the thigh to the knee.
The course of the nerve can vary from person to person, and even from side to side in the same person. This variability in the path of nerve might make some people more vulnerable to this condition than others.
The symptoms of lateral femoral cutaneous nerve syndrome are a variety of unpleasant sensations in the area of the nerve. These sensations have been described as pain, numbness, tingling, burning, itching, sensitivity, or some combination of all of these. These symptoms are sometimes worse after walking or standing. Sitting can either relieve or worsen the pain, depending on the patient.
The lateral femoral cutaneous nerve’s job is to provide sensory information. Unlike the sciatic nerve, this nerve does not control any muscles – so weakness or changes in the reflexes are not involved in this syndrome. About 80 per cent of the cases affect only one leg. There are situations where both legs are affected, but that tends to be associated with other abdominal diseases or multiple abdominal surgeries.
The syndrome has been blamed on a variety of causes. It can occur due to compression of the nerve by something as common as clothing or belts. Biomechanical factors such as a leg-length difference or a pelvic tilt can also lead to this syndrome.
Symptoms may appear immediately after a seatbelt-related injury or as a complication of many abdominal surgeries.
It can also occur secondary to hormonal diseases such as diabetes, and it may be the initial symptom of an underlying illness, such as chronic appendicitis.
To further complicate the picture, conditions affecting the spine can mimic the syndrome. Lumbar disc herniation, osteoarthritis, and spinal stenosis can all have similar symptoms.
Damage to the nerve can occur from such common conditions as obesity and pregnancy, both of which involve abdominal enlargement. It appears that simply having a large abdomen can exert enough traction of the nerve to cause the syndrome.
Treatment begins with conservative measures. The first line of treatment is usually advice on the need to wear loose clothing and weight loss. Stimulation of the nerve by a trained professional can be very helpful. A good self-care option is the application of moist ice over the area where the nerve emerges from the pelvis.
Treatment of this syndrome has not been studied yet by the usual method of randomized controlled trials. Failure to respond conservative treatment may be augmented by steroids and certain epilepsy drugs know to relieve nerve pain. Surgery to relieve this condition is reserved as a last resort.